puberty
the changes that occur in boys and girls around the age of 10 to 14, which signify the beginnings of sexual maturity and the subsequent functioning of reproductive organs. It is apparent through the appearance of SECONDARY SEXUAL CHARACTERISTICS , such as a deepening of the voice in boys and growth of BREASTS in girls. In addition, girls commence MENSTRUATION and in boys the size of TESTICLES increases. In both sexes body shape changes noticeably and body hair grows. The changes are initiated by PITUITARY GLAND hormones acting on the ovaries ( see OVARY ) and testes.
Puberty is the time in life when a boy or girl becomes sexually mature. It is a process that usually happens between ages 10 and 14 for girls and ages 12 and 16 for boys. It causes physical changes, and affects boys and girls differently.
In girls:
- The first sign of puberty is usually breast development.
- Then hair grows in the pubic area and armpits.
- Menstruation (or a period) usually happens last.
In boys:
- Puberty usually begins with the testicles and penis getting bigger.
- Then hair grows in the pubic area and armpits.
- Muscles grow, the voice deepens, and facial hair develops as puberty continues.
Both boys and girls may get acne. They also usually have a growth spurt (a rapid increase in height) that lasts for about 2 or 3 years. This brings them closer to their adult height, which they reach after puberty.
NIH: National Institute of Child Health and Human Development
puberty